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Diffstat (limited to 'ast/erfa/s2pv.c')
-rw-r--r-- | ast/erfa/s2pv.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/ast/erfa/s2pv.c b/ast/erfa/s2pv.c new file mode 100644 index 0000000..df6e1c7 --- /dev/null +++ b/ast/erfa/s2pv.c @@ -0,0 +1,112 @@ +#include "erfa.h" + +void eraS2pv(double theta, double phi, double r, + double td, double pd, double rd, + double pv[2][3]) +/* +** - - - - - - - - +** e r a S 2 p v +** - - - - - - - - +** +** Convert position/velocity from spherical to Cartesian coordinates. +** +** Given: +** theta double longitude angle (radians) +** phi double latitude angle (radians) +** r double radial distance +** td double rate of change of theta +** pd double rate of change of phi +** rd double rate of change of r +** +** Returned: +** pv double[2][3] pv-vector +** +** Copyright (C) 2013-2016, NumFOCUS Foundation. +** Derived, with permission, from the SOFA library. See notes at end of file. +*/ +{ + double st, ct, sp, cp, rcp, x, y, rpd, w; + + + st = sin(theta); + ct = cos(theta); + sp = sin(phi); + cp = cos(phi); + rcp = r * cp; + x = rcp * ct; + y = rcp * st; + rpd = r * pd; + w = rpd*sp - cp*rd; + + pv[0][0] = x; + pv[0][1] = y; + pv[0][2] = r * sp; + pv[1][0] = -y*td - w*ct; + pv[1][1] = x*td - w*st; + pv[1][2] = rpd*cp + sp*rd; + + return; + +} +/*---------------------------------------------------------------------- +** +** +** Copyright (C) 2013-2016, NumFOCUS Foundation. +** All rights reserved. +** +** This library is derived, with permission, from the International +** Astronomical Union's "Standards of Fundamental Astronomy" library, +** available from http://www.iausofa.org. +** +** The ERFA version is intended to retain identical functionality to +** the SOFA library, but made distinct through different function and +** file names, as set out in the SOFA license conditions. The SOFA +** original has a role as a reference standard for the IAU and IERS, +** and consequently redistribution is permitted only in its unaltered +** state. The ERFA version is not subject to this restriction and +** therefore can be included in distributions which do not support the +** concept of "read only" software. +** +** Although the intent is to replicate the SOFA API (other than +** replacement of prefix names) and results (with the exception of +** bugs; any that are discovered will be fixed), SOFA is not +** responsible for any errors found in this version of the library. +** +** If you wish to acknowledge the SOFA heritage, please acknowledge +** that you are using a library derived from SOFA, rather than SOFA +** itself. +** +** +** TERMS AND CONDITIONS +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions +** are met: +** +** 1 Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** +** 2 Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in +** the documentation and/or other materials provided with the +** distribution. +** +** 3 Neither the name of the Standards Of Fundamental Astronomy Board, +** the International Astronomical Union nor the names of its +** contributors may be used to endorse or promote products derived +** from this software without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +** POSSIBILITY OF SUCH DAMAGE. +** +*/ |